Foreign direct investment has traditionally been viewed as a key driver of prosperity, and modern FDI has also become a vehicle for transferring intangible assets. This column uses a counterfactual experiment based on a hypothetical world with no outward or inward FDI to and from low-income and lower-middle-income countries to examine the effects of FDI on trade, domestic investment, and welfare. World welfare falls by about 6% and all countries lose out, with some poorer countries losing over 50%. World trade falls by 7%, with the losses again unevenly distributed.

Artificial intelligence promises economic growth as well as creating fear for those whose jobs it may replace. This column takes a wider approach to examining how AI and other technologies will affect citizens’ welfare beyond just their income. It argues that the new technologies are intrinsically neither good nor bad, it is how they are deployed and how the transition is crafted that conditions the welfare dynamics of societies.

Launched in 2006, Medicare Part D allows beneficiaries to enrol in subsidised drug coverage plans sold by private insurers, but navigating the different plans can be complex and lead to sub-optimal choices. This column uses Medicare administrative data for 2006-2010 to understand the quality of consumer decision-making in the Part D marketplace. It finds that the vast majority of elderly place too much weight on premiums relative to out-of-pocket costs, care a great deal about the particular combination of plan features, and are highly likely to choose the same plan every year regardless of changes in prices and alternatives.

Trade in intermediates (or ‘unbundling of production') and trade in capital have become increasingly important in last 25 years. This column shows that trade in intermediates generates a reallocation of capital across countries that exacerbates world inequality in both income and welfare. Unbundling of production hurts middle-income countries but helps those with high productivity. Trade in intermediates also increases within-country inequality, and this increase is U-shaped in the aggregate productivity level of the country.

For the optimal design of social insurance policy, policymakers must consider how public insurance interacts with family dynamics. This column reveals how in Austria, the impact of husbands losing their jobs on wives entering the workforce is generally weak compared to other countries. This may be explained by traditional gender norms and the importance of the male breadwinner model.

Many economic disruptions create winners and losers. This column presents an analytical formula for tax reform to offset welfare losses by redistributing the winners’ gains when tax instruments are distortionary and wages are endogenous. It shows how the model can be applied to empirical data, for example to offset the impact of robots in the US and Germany.

Changing the terms and rules governing welfare can have substantial effects on employment. This column explores how the imposition of time limits for welfare receipt affected the employment, marriage, and divorce rates of women in the US. As intended by the reform, time limits decreased welfare use and the divorce rate, while increasing employment. Despite this, those women who were worst off prior to the reform are found to be even worse off after it.

Unemployment insurance is compulsory in almost all countries, with no choice for workers over the level of coverage. But why restrict choice if it can improve the targeting of individuals who value the insurance the most? This column uses evidence from Sweden to examine whether the issue of adverse selection justifies a universal mandate for unemployment insurance. Workers who purchased more generous unemployment insurance were more than twice as likely to be unemployed in the following year. A universal mandate combats such adverse selection, but forces workers to buy insurance even when insurance costs are higher than the value they assign to it.

Indians, and in particular men seeking education and jobs, display a puzzling reluctance to cross state borders. This column explores the reasons for this surprising migration pattern. A major culprit is India’s system of ‘fragmented entitlements’, whereby welfare benefits are administered at the state level, and state residents get preferential treatment when it comes to higher education and government employment. These administrative rules prevent the more efficient allocation of labour across the country.

In medical treatment, it is assumed that adherence to clinical practice guidelines is always preferable to decentralised clinical decision-making, yet there is no welfare analysis that supports this belief. This column argues that it would be better to treat clinical judgement as a problem of decision-making under uncertainty. In this case there would be no optimal way to make decisions, but there are reasonable ways with well-understood welfare properties.

Research on economic mobility has failed to disentangle the underlying economic drivers. In particular, opportunities for upward movement represent welfare-enhancing mobility, while risky income shocks represent welfare-reducing mobility. This column presents a framework for differentiating between these factors, and applies the model to Mexican data. Results show that opportunity and risk are equally important drivers of income mobility, with large but opposing welfare effects. This challenges the idea that societies with higher measured income mobility are better.

Past studies have measured poverty in either relative terms (mostly in the developed countries) or absolute terms (the developing world). This column presents a new unified approach to global poverty that assumes that people care about both their own income and their income relative to others in their country of residence. The study finds that global poverty has declined more in absolute terms than in relative terms. The vast bulk of the relatively poor now live in the developing world. The advanced countries have seen little progress against poverty, unlike the developing world.

Despite the long-held belief that high levels of inequality in the US signal future opportunity, a number of studies suggest that this is no longer the reality. This column examines trends in inequality from the perspective of well-being and focuses on non-economic aspects of welfare, including hope. The results reveal stark differences across people, races, and places in the US. Poor minorities – and blacks in particular – are much more hopeful than poor whites, while urban places are more hopeful than are rural ones, as are places with higher levels of diversity.

Childcare subsidy provision in the US remains substantially lower than in many other developed economies. This column compares the potential effects of expanding three existing subsidy programmes in the US. It also argues, however, that amassing majority support for the expansion of any of the programmes would be difficult given the relatively few number of households the transfers benefit.

In the 2012 US presidential election, Mitt Romney famously asserted that 47% of the population were long-term dependents of the government – ‘takers’, not ‘givers’ to the system. This column examines this claim using long-spanning household-level data. Even though many households find themselves not paying tax or receiving public benefits in at least some years, only a small fraction consistently pay no tax or consistently receive public transfers.

Trade economists typically believe that in addition to lower prices for imported goods, trade liberalisation also brings import variety and domestic productivity gains. This column accounts for these ‘new’ gains in a careful reconsideration of the Canada-US Free Trade Agreement. Although the agreement did see improvements in Canadian income associated with import variety and domestic productivity, these were far outweighed by the welfare loss associated with the reduction in domestic variety. Nonetheless, Canadian welfare did improve overall when one takes into account the ‘traditional’ gains associated with lower import prices.

Governments have long used taxation to correct for the socially costly overconsumption of alcohol, but as the external cost of overconsumption varies across drinkers, a single tax rate is not optimal. This column argues that variation in preferences for different products and in price responsiveness across heavy and light drinkers provides scope to improve welfare by varying tax rates across alcohol products. The proposed framework is well suited to addressing other sources of external costs, such as obesity.

The Unemployment Insurance programme in the US was significantly expanded during between 2008 and 2014. This column examines the effect of unemployment insurance duration on aggregate employment during the Great Recession using state-level expansions and contractions in insurance generosity. It finds a positive but not statistically significant employment impact of expanding the insurance. This suggests that the substantial insurance value of the extensions during the Great Recession was not offset in any meaningful way by any costs from weaker job growth.

Temporary job contracts account for a substantial proportion of the workforce in countries such as France and Spain, but they can result in high job turnover and instability. This column assesses the impact of government policies that impose taxes on temporary contracts to induce employers to lengthen job durations. Such policies a negative impact on the labour market, reducing the mean duration of jobs and decreasing job creation. The introduction of open-ended contracts with no termination cost for separations occurring at short tenure may be more effective.

Upward social mobility is widely sought but often elusive in highly mobile societies like the US. While previous work has focused on intergenerational transmission of income levels and social prosperity among natives and immigrants, this column studies the intergenerational transmission of health. There is substantial persistence in health status for both natives and immigrants. However, as immigrant families remain in the US for more generations, their children’s health tends to resemble more the health of native children and less the health of their mothers.